A project to restore a long-shuttered, historic former South End hotel cleared an important hurdle Thursday as the Boston Planning and Development Agency (BPDA) signed off on plans to redesign and significantly expand the decaying building.

The support now puts developer Alexandra Partners LLC closer to seeing out a vision to transform the Hotel Alexandra back to its former glory by making it home to a 12-story, 150-room boutique hotel while keeping its 1875 Gothic-style facade intact.

Plans show the project would include using vacant land on an adjacent property to bring the five-story building to new heights. A rooftop bar and restaurant and cafe space are planned for the hotel.

“The Hotel Alexandra building is one of the few remaining historic structures along Washington Street in the blocks immediately west of Massachusetts Avenue, and has experienced significant water and fire damage over the many years it has been vacant and could lead to permanent loss if the current state of neglect were to continue,” reads a project notification form filed in late 2018.

The Hotel Alexandra as it currently stands at the corner of Washington Street and Massachusetts Avenue in the South End.As part of their approval from the board, developers have agreed to work with Madison Park Technical School to create a co-op program for students to gain experience in the construction, hotel, and restaurant industries, according to the agency.

The hotel will make its amenities open to the public, install indoor bike racks for its employees, and will subsidize their MBTA Charlie Cards, officials said. Complimentary cards will be given to guests.

“The project will not include on-site parking, but will make improvements to the Silver Line stop and surrounding public realm,” the BPDA said in a statement.

The board’s approval came a day after City Councilor At-Large Althea Garrison filed a resolution seeking to enforce the city’s zoning code to lessen the height of the building, an issue she said she’s heard concerns about from “countless residents.”

Her proposal also seeks to have the renovation fall under the purview of “the by-laws that direct the South End/Roxbury Landmarks District.”

“The use of predominantly glass towers cannot be considered a compliment to the Victorian housing around it, but rather, a contrasting and distracting focal point,” Garrison said.

The resolution received swift pushback from several councilors Wednesday, including Kim Janey, who represents the district where the hotel stands.

“I have received, just to date, close to 100 emails from South End and Roxbury residents and the vast majority of those are in support of the project,” she said. “Now, for decades the site of the Hotel Alexandra has been an eyesore and a blighted piece of property … it’s been a missed opportunity to bridge the gap between the South End and Roxbury.”

The resolution was assigned to the Committee on Planning, Development, and Transportation for review.

What exactly the future holds for the historic hotel property has been up in the air in recent years after the Church of Scientology, which purchased the site for $4.5 million in 2008, put it on the market in 2015.

A Letter of Intent for the current redevelopment project was filed in July 2018 by JB Ventures and TCR Development, whose principals are now working under the name Alexandra Partners, documents show.

The project calls for replacing the aging building’s structural components due to their condition. With the anticipated additions, the new hotel would contain 66,000 square feet with possibly a basement gym for guests, the plans indicate.

Bonnie McGilpin, director of communications for the BPDA, told Boston.com Friday that the project still must be reviewed by the Zoning Board of Appeals and the Landmarks Commission.